An Analysis of Individual Differences in Within-Test Practice Effects in Progressive Matrices

The present study aimed to investigate individual differences in practice effects during progressive matrices based on Carpenter et al.'s taxonomy of abstract rules. To this end, data from a non-verbal reasoning test, the Abstract Reasoning Test (ART), were used. Because the ART was developed from Carpenter et al.'s theory, the impact of extraneous factors unrelated to the theoretical model is minimized, thereby allowing for a more precise identification of practice effects. The sample consisted of 765 military recruits who responded to 34 items on the ART. Analyses were conducted using a random weights operation-specific learning model (RWOSLM), in which practice parameters were treated as random effects allowed to vary across individuals. The model measures within-test practice effects specific to each examinee, allowing the hypothesis of rule learning during the ART to be assessed at the individual level. Correlations between practice effects and external measures associated with intelligence were examined to investigate the nature of the practice effects. The results suggest individual differences in rule learning within the ART. Decreases in difficulty were observed for both pairwise progression and figure addition or subtraction, although between-person variability was evident only for the latter. Additionally, the results revealed between-person variability in decreases in difficulty associated with one of the items' figural properties, which suggests the existence of individual differences in the process of increasing familiarity with this feature throughout the test. Individual differences in practice effects during the ART significantly correlated with external measures of abilities and intellect, suggesting that practice effects during progressive matrices are conceptually tied to intelligence.